Private replies to forum posts

User feedback: "It would be good to be able to click someones name from a forum post and be able to private message them. At least there should be an option for a poster to choose if they want to be able to be contacted or not....maybe tick a box when posting."

It would only be possible to reply to posts from contacts - would that restriction be confusing?

How should the context of the reply be shown? There's a risk of confusing the users about who can see which parts of the conversation.